Get Ready for REST

REST API usage prerequisites are described in this section. These prerequisites will enable REST v3 applications to run with Accelerator. Some of the prerequisites apply to the Accelerator queue configuration and others apply to the host where the REST application will run, also called the "submit host".

Prerequisites for the Accelerator queue:
  • The web port must be configured. In version 2021.2.0 through 2022.1.1, the web provider must be set to "internal". See the -webport and -webprovider options in the -h help screen documentation for VOV project start commands like ncmgr start and lmmgr start.
  • Optional: SSL/TLS should be enabled for security reasons. Since passwords are passed with HTTP authorization requests to vovserver, the security of the connection is important. Enable SSL/TLS for the NC queue as follows:
    1. Add this line to SWD/policy.tcl:
      set config(ssl.enable) 1
    2. If REST requests will be sent from Python scripts running on CentOS 7 or earlier, TLS 1.2 will be used by the REST application you are writing. Configure vovserver to accept TLS 1.2 protocol by adding the following line to SWD/policy.tcl:
      set config(http.minSSLVersion) "TLSv1.2"
    3. Optional: Append a line to SWD/setup.tcl that sets VOV_HOST_HTTP_NAME to the fully qualified host name (FQHN) where vovserver is running. The FQHN is the output of hostname -f.
      setenv VOV_HOST_HTTP_NAME FQHN
    4. Optional: For a full HTTPS security, a CA-signed domain-wide SSL certificate is installed in $VOVDIR/local/ssl or a host-specific CA-signed SSL certificate is installed in SWD/config/ssl. This will allow your REST network traffic to be fully secured. See Advanced REST Usage for more about this.
    5. Reread and activate the changed server configuration parameters via vovproject reread or similar commands.
Prerequisites for the submit host:
  • The submit host must have network access to the server running the NC queue.
  • Python version 3 or higher is required to use the vov_rest_v3.py REST access library module.
  • The Python "requests" package must be installed.
  • Copy vov_rest_v3.py from $VOVDIR/scripts/python/vov_rest_v3.py to the directory on the submit host where your Python application resides.